The present invention relates generally to consumer electronic devices, and particularly to loudspeakers for consumer electronic devices.
Many consumer electronic devices are equipped with one or more integrated speakers that project audible sound to a user. Some cellular telephones, for example, have two speakers. The first speaker projects audible sound through a sound port that a user places next to an ear when communicating with a remote party. The second speaker, which projects sound through another sound port, permits the user to employ the device as a speakerphone or as a music playback device.
Manufacturers commonly orient their second speakers to project the audible sound through a sound port located in the rear of the housing. Such placement prevents undesirable feedback with a microphone port, which is usually located on the front of the housing, and allows the manufacturer to use the limited space within the cellular telephone. However, some cellular telephones may have relatively poor quality speakers and/or microphones. Therefore, users of these devices must sometimes flip the cellular telephone between the back and the front so that they can both hear and speak to a remote party. This is particularly burdensome when the user communicates with remote parties in a hands-free mode.
Some manufacturers address this problem by re-routing the audible sound towards the front of the device. For example, one particular “clam shell” type cellular telephone—the i95 manufactured by MOTOROLA—conventionally orients a speaker towards the rear of the device. Audible sound projected by the speaker enters a pair of specially designed waveguides. The waveguides re-direct the audible sound towards the front of the device and through corresponding sound ports disposed on either side of a keypad.
The waveguides and corresponding ports are additional specialized parts, and thus, may cost more to manufacture. In addition, they may hinder design efforts to reduce the form factor of the device. This latter aspect may be especially problematic in certain types of cellular telephones such as “sliding” type cellular telephones.